Experimenting with hydroelastic contacts in MuJoCo

[acyclics]

Hi, I’m interested in experimenting with hydroelastic contact modeling in MuJoCo. I came across this article, which provides a great overview of hydroelastic contacts and their potential benefits for robotic applications.

I’m still getting familiar with the MuJoCo codebase, so I’d appreciate any guidance on how to begin integrating a new contact model. Additionally, if the integration goes well, what would the process look like for contributing a feature such as an alternative contact model back to MuJoCo?

[kevinzakka]

You might find this relevant: https://github.com/ubi-agni/mujoco_contact_surfaces

[yuvaltassa]

A new contact model is a pretty complicated contribution, but not impossible to imagine 🙂

Let's first get to the point where you have something working that appears to be valuable and then discuss what a chain of PRs would look like. The challenge is to break it up into self-contained and well tested PRs.

[quagla]

I would claim that the hardest part is the geometry intersection part. Then you probably have to figure out if this contact model can be implemented simply as a passive force / velocity filter. MuJoCo contact uses a constraint solver, which is more complicated than that, but if your model is "just" an additional force it would simplify things a lot.